I know I can leave my tanks and they will probably be fine but I really am hoping this other idea works. The tank with my main concern is my new 10 gallon fry tank. It has 30 or so fry (mix of guppy, molly, and platy) I really don't want to leave them for a week without food. I found out today that they all seem to pick at the Seaweed salad stuff and eat that. (Its basically those sheets of algae) Do I need to worry about these sheets polluting my water? I can't imagine I would since its just algea but what are your thoughts? I think I can put a pretty small piece in and they would have enough to munch on all week. By the time they eat it all I would be back in a couple days. If it doesn't dissolve like those weekend feeders in your water I may just have to put some in my other tanks as well.